Conduction Disturbances Research Articles

Computed tomographic predictors of conduction disturbances following TAVI using the Evolution Series

Computed tomographic predictors of conduction disturbances following TAVI using the Evolution Series

Impact of New-Onset Conduction Disturbances following Transcatheter Aortic Valve Replacement on Outcomes: A Single-Center Study.

Transcatheter aortic valve replacement (TAVR) is known to increase the incidence of conduction disturbances compared to surgical aortic valve replacement; however, there are limited data on the impact and duration of these conduction disturbances on longer term outcomes. To determine the differential impact of persistent versus nonpersistent new-onset conduction disturbances on TAVR-related complications and outcomes. This is a single-center retrospective analysis of 927 consecutive patients with aortic stenosis who underwent TAVR at Yale New Haven Hospital from July 2012 to August 2019. Patients with new-onset conduction disturbances within 7 days following TAVR were selected for this study. Persistent and nonpersistent disturbances were, respectively, defined as persisting or not persisting on all patient ECGs for up to 1.5 years after TAVR or until death. Within 7 days after TAVR, conduction disturbances occurred in 42.3% (392/927) of the patients. Conduction disturbances persisted in 150 (38%) patients and did not persist in 187 (48%) patients, and 55 (14%) patients were excluded for having mixed (both persistent and nonpersistent) disturbances. Compared with nonpersistent disturbances, patients with persistent disturbances were more likely to receive a PPM within 7 days after the TAVR procedure (46.0% versus 4.3%, p < 0.001) and had a greater unadjusted 1-year cardiac-related and all-cause mortality risk (HR 2.54, p=0.044 and HR 1.90, p=0.046, respectively). Persistent conduction disturbances were associated with a greater cardiac and all-cause mortality rate at one year following TAVR. Future research should investigate periprocedural factors to reduce persistent conduction disturbances and outcomes beyond one year follow-up.

Performance of the 2019 consensus algorithm on the management of conduction disturbances after TAVI in clinical practice

Introduction and objectivesConduction disturbances (CD) after transcatheter aortic valve implantation (TAVI) increase the risk of permanent pacemaker (PPM) implantation and often preclude early-discharge (ED). The aim of this study was to evaluate the performance of the 2019 consensus algorithm on the management of conduction disturbances post-TAVI in a real-world cohort. MethodsRetrospective analysis of patients who underwent transfemoral TAVI between 2016 and 2018. Patients with prior PPM were excluded. The algorithm classified patients as ED or non-ED candidates (due to a higher risk for high-degree atrioventricular block or because they were eligible for PPM). ED was defined as discharge at day-3 post-TAVI. Primary endpoint was the 30-day rate of PPM implantation and secondary endpoints included 6-month pacing rate, 1-year rate of syncope and all-cause mortality and the composite outcome of both, regarding ED eligibility. ResultsA total of 220 patients were included. The algorithm classified 66% of the patients as ED candidates. The 30-day rate of PPM implantation was 3.6% for ED candidates (vs 62.5% for non-ED candidates; P<.001). No differences were found in the secondary endpoints between ED and non-ED candidates. The algorithm identified 16% of the patients as eligible for PPM of whom 97.1% underwent PPM implantation; 18% of the patients were classified as at higher risk of high-degree atrioventricular block. ConclusionsThe 2019 algorithm allowed to safely ED a significant number of patients with conduction disturbances post-TAVI and to identify patients with a clear indication for PPM implantation. However, in high-risk patients, the algorithm does not provide a guiding strategy.

A Modeling and Design Methodology of Double Exponential Pulse Generator for Simulation-Based Conducted Disturbance Immunity Testing

In this paper, an equivalent circuit model of a double-exponential pulse generator is proposed for use as a time-domain noise source in high-altitude electromagnetic pulse (HEMP) conducted disturbance immunity testing. The analytic relationship between the proposed equivalent circuit model and the source pulse requirements expressed by the test standards is derived. Based on this relationship, a design methodology for the equivalent circuit model is proposed to extract the circuit components that satisfy the source pulse requirements, particularly in the form of source impedance and pulse waveform requirements. The proposed design methodology is applied to design an equivalent circuit model of the double exponential pulse generator with various test modes in the conducted disturbance immunity test. The designed double exponential pulse generator is applied to a simulation-based conductive disturbance immunity testing platform based on the International Electrotechnical Commission (IEC) 61000-4-24 standard to validate the effectiveness of the proposed equivalent circuit model and design methodology.

Invasive electrophysiology study guided loop recorder implantation in myotonic dystrophy type 1: a prospective single-center study

Abstract Funding Acknowledgements Type of funding sources: None. Introduction In one third of the patients with myotonic dystrophy type 1 (DMT1) the cause of death is of cardiac origin. The most common cardiac manifestations are arrhythmias and conduction disturbances. Purpose Due to its extreme long monitoring properties, implantable loop recorders (ILRs) are highly suitable to detect rare cardiac arrhythmias. To date, there are only limited data using ILRs in DMT1. We aimed to evaluate the role of the invasive electrophysiology study (EPS)-guided loop recorder implantation in patients with DMT. Methods In our prospective study 18 genetically confirmed DMT1 patients underwent non-invasive cardiac examination including transthoracic echocardiography, 24-hour Holter monitoring and surface ECG. In addition, EPS was performed in all cases to evaluate the risk of sudden cardiac death and infra-Hisian conduction properties. Based on the performed non-invasive diagnostic evaluation and EPS findings, patients were divided into low, intermediate and high-risk groups. For patients with normal investigation results and normal HV interval (&amp;lt;55 ms) only annual cardiac follow-up visits were planned (low-risk group). Patients with increased PR interval (&amp;gt;240 ms), QRS duration (&amp;gt;120 ms), or slightly prolonged HV interval (55-70 ms) underwent implantable loop recorder (ILR) implantation (intermediate-risk group). Permanent pacemaker (PM) or implantable cardiac defibrillator (ICD) was implanted in patients with 2nd/3rd degree atrioventricular block (AVB), significantly prolonged HV interval (&amp;gt;100 ms) or if sustained ventricular tachyarrhythmia could be induced during EPS. All patients were followed for at least 3 years. Results According to our study criteria, 8 patients could be categorized as "intermediate risk", 7 of them received implantable loop recorder (ILR). 1 ILR had to be removed 3 weeks after implantation due to skin infarction. During three-years of follow-up, 2 patients had many asymptomatic atrial high-rate episodes, but no 2nd or 3rd degree AVB, significant asystole or malignant ventricular arrhythmia were detected. Conclusions Our single-center prospective study examined the EPS-guided ILR implantation for the risk stratification of DMT1 patients for the first time. A more extensive, multicenter study is warranted to define optimal management of DMT1 patients with slightly impaired infrahisian conduction.

Etiological and molecular determinants of atrial endomysial fibrosis: results from the CATCH ME consortium

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – EU funding. Main funding source(s): CATCH ME: Characterizing Atrial fibrillation by Translating its Causes into Health Modifiers in the Elderly Background We recently demonstrated that in human atria, endomysial fibrosis causes conduction disturbances during atrial fibrillation (AF), while overall connective tissue content (over-all fibrosis) has no effect. Etiological and molecular determinants of endomysial fibrosis are largely unknown. Methods We quantified over-all and endomysial atrial fibrosis using staining with WGA in left (LA, n=95) and right (RA, n=76) atrial appendages sampled from a European cohort (CATCH ME) of patients undergoing cardiac surgery. The contributions of AF, heart failure (HF), sex, age, and 4 principal components accounting for confounding clinical characteristics to over-all and endomysial fibrosis were determined in a multivariate model. RNA sequencing was performed to explore biological pathways associated with the two types of fibrosis. Results Over-all and endomysial fibrosis were moderately correlated (LA: r=0.69, RA: 0.61, both p&amp;lt;0.001) and more pronounced in RA than in LA samples (p&amp;lt;0.001). In LA, persistent AF, female sex, and HF were independently associated with endomysial fibrosis, while over-all fibrosis was only associated with sex and HF. Likewise, in RA, persistent AF was associated with endomysial fibrosis, while over-all fibrosis was not. Expression of 18 genes was univariately associated with endomysial fibrosis in LA but only 1 in RA. There were no genes associated with over-all fibrosis. After correction for relevant clinical traits, BMP10 showed the strongest association with endomysial fibrosis amongst coding genes (p=3.16E-04, LA). In an independent validation cohort (RACE V Tissue Bank Project, n=162 pts undergoing cardiac surgery), out of 11 biomarkers reflecting inflammation, fibrosis, vascular dysfunction, or ischemia, BMP10 plasma levels were most strongly associated with endomysial fibrosis (p&amp;lt;0.001), but not with over-all fibrosis. Conclusions Taken together, female sex, HF, and AF are the main drivers of fibrosis in human atria. However, endomysial fibrosis is independently associated with AF whereas over-all fibrosis is not. BMP10 is a specific marker of endomysial fibrosis. Our findings suggest that distinct mechanisms are involved in the development of over-all versus endomysial fibrosis in human atria and may provide an explanation for the recently reported predictive value of BMP10 biomarkers levels for AF recurrences after AF ablation and for stroke.

Deep learning to diagnose left ventricular hypertrophy from standard, 12-lead ECG signals: a proof-of-concept study

Abstract Funding Acknowledgements Type of funding sources: None. Background Although several sets of voltage and non-voltage criteria have been employed to detect left ventricular hypertrophy (LVH) in 12-lead electrocardiogram (ECG) signals, their accuracy has been proven suboptimal, while their use is limited by the lack of expertise of most non-specialised caregivers. Deep learning (DL) can be employed as an integrated, automated solution, yielding high predictive power for this task. Purpose To train a DL model to diagnose LVH from 12-lead ECG signals and evaluate its diagnostic performance. Methods A total of 21,837 previously annotated ECG samples were retrieved from the PTB-XL database. Of them, 2,137 (9.8%) had a diagnosis of LVH, while the remaining 90.2% presented with other abnormalities, including non-specific ST changes and conduction disturbances. After applying discrete wavelet transformation to denoise signals (remove the baseline drift and fine noise), we applied a dedicated convolutional, time-series-dedicated neural network (InceptionTime), which we trained on 90% of the data. We reserved the remaining 10% of "unseen" samples for testing its performance and quantifying its recall (sensitivity), precision, F1-score (harmonic mean of recall and precision) and area under the curve (AUC). We employed k-fold cross-validation and repeated the same procedure 10 times, to obtain distributions for each metric score. Results The 10 training/testing iterations yielded a median recall of 0.78 (interquartile range, IQR: 0.70-0.91) and a median precision of 0.78 (IQR: 0.75-0.87), indicating the predictive power of the model to both correctly detect LVH when it exists and also not falsely overdiagnose it, missing less than 1 out of 4 cases, in both scenarios. The obtained F1-score was 0.8 (IQR: 0.76-0.83) and the median AUC was 0.86 (IQR: 0.83-0.91). Conclusions Although a proof-of-concept study, this attempt demonstrates the potential of DL approaches to accurately detect heart abnormalities, such as LVH, from standard ECG recordings. Such strategies can not only support non-specialist physicians in picking diagnoses hidden "in plain sight", but they can also offer high diagnostic performance, given that attempts are made to optimize them. Toward this direction, our concept work shows that even a simple DL approach, without rigorous optimization, can display high predictive power, misdiagnosing less than 22% of the cases, paving the way for the improvement of such techniques and their integration in clinical practice.

Long-term impact of pacemaker implantation after TAVI: a subgroup analysis according to previous intraventricular conduction disturbances

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Transcatheter aortic valve implantation (TAVI) is a worldwide accepted treatment for severe aortic stenosis (AS). Conduction system disturbances, frequently requiring permanent pacemaker (PM) implantation, remain one of the most common procedural complication. Whether the permanent ventricular pacing has a deleterious impact on the prognosis of this population remains unclear. Objectives To assess the long-term impact of permanent PM implantation in clinical outcomes after TAVI. Methods We performed a retrospective analysis of consecutive patients (P) who underwent TAVI between 2009 and 2021 in a single tertiary center.P with a PM implanted before TAVI or with in-hospital mortality were excluded from the analysis. PM implantation post-TAVI was defined as an implant during hospital stay after TAVI or in the first month after discharge. Kaplan Meier survival curves were used to estimate the impact of permanent PM after TAVI, regarding the composite endpoint of all-cause mortality and heart failure (HF) hospitalization during a 4 years follow-up period, and a comparison performed according to the presence or absence of baseline intraventricular conduction disturbances. Results 549 P (82±6.6 years, 56.8% female, left ventricular ejection fraction 53±10%, peak gradient 51±15.6 mmHg, aortic valve area 0.7± 0.2 cm2) were included. At baseline, 108 P (20%) had intraventricular conduction disturbances on ECG (50 P with right bundle branch block [RBBB] and 58 P with left bundle branch block [LBBB]). 127 P (23%) required PM implantation after TAVI. Baseline characteristics were similar between P with and without PM implantation, except for age, gender, previous valvular surgery and RBBB (Table 1). At 48 months follow-up, 35% (n=193) met the composite endpoint, that was similar between both groups (35.8% vs. 34.1%, p=0.731). Kaplan-Meier survival curves revealed no difference in the composite endpoint between the two groups (log-rank p=0.170). Further analysis of subgroups according to the presence or absence of baseline intraventricular conduction disturbances revealed a significant difference among the subgroup of P without previous intraventricular conduction disturbances that underwent PM implantation after TAVI (log rank p=0.02) (Fig 1). This difference in the composite endpoint after PM was not found in the subgroups of P with RBBB (log rank p=0.656) or LBBB (log rank p=0.975) at baseline (Fig 2).* Conclusions Permanent PM implant after TAVI does not have an impact on long-term HF hospitalization and mortality. However, in the specific subgroup of P without previous intraventricular conduction disturbances, PM implantation seems to be associated with worse prognosis.

Left bundle branch area pacing guided by electroanatomical mapping in patients with structural heart disease and advanced conduction abnormalities

Abstract Funding Acknowledgements Type of funding sources: None. Background Left bundle branch area pacing (LBBAP) can be technically challenging and fluoroscopy-intense, particularly in patients with structural heart disease (SHD) and advanced conduction abnormalities. Three-dimensional electroanatomical mapping (EAM) facilitates high-resolution, real-time, and non-fluoroscopic lead navigation, electrogram and pace mapping. Purpose The purpose of the study was to prospectively evaluate the feasibility, safety, and outcomes of routine EAM-guided LBBAP in patients with SHD and advanced conduction abnormalities. Methods Consecutive patients with SHD and advanced conduction abnormalities (defined as second or third-degree atrioventricular (AV) block and/or complete bundle branch block) who underwent an attempt at EAM-guided LBBAP were included. EAM-guided lead implantation was performed in all patients following a standardized protocol irrespective of the pacing indication and type of conduction disturbance. The feasibility, safety, procedural and mid-term outcomes were evaluated. Electrical, echocardiographic, and clinical parameters were assessed at implantation and last follow-up. Results Thirty-two patients (68±18 years; 19% female) were included. The indication for pacing was cardiac resynchronization therapy in 50%, AV block in 44%, and pace-and-ablate in 6% of patients; 24 patients (75%) had an intrinsic QRS &amp;gt;150 ms, 17 (53%) had LBBB. Primary EAM-guided LBBAP was successful in 29 patients (91%). Procedural duration was 95 (70-110) min, total fluoroscopy time 0.93 (0.40-1.73) min, and total fluoroscopy dose 35.4 (20.5-77.2) cGycm2 (Figure 1A). The paced QRS duration during LBBAP was significantly shorter than the baseline intrinsic QRS duration (121.9±10.7 vs. 159.2±34.4 ms; p&amp;lt;0.001) (Figure 1B) and remained stable (120.3±11.1 ms; p=0.370) during a mean follow-up of 7.0±5.9 (median 5.4 [IQR 2.1-12.6]) months. LBBAP capture threshold was 0.57±0.23V/0.4ms at implantation and remained low during follow-up (0.58±0.18V/0.5±0.2ms; p=0.877). There was no increase in LBBAP capture threshold &amp;gt;1.0V/0.4 ms during follow-up. Overall LVEF improved significantly from 44.2±14.3% at baseline to 49.4±13.1% at last follow-up (p=0.009), NYHA functional class from 2.4±0.6 to 1.8±0.6 (p=0.002), respectively (Figure 1C+D). No complications occurred that required intervention. Conclusion Routine near-zero fluoroscopy EAM-guided LBBAP can safely be performed in patients with SHD and advanced conduction abnormalities with high success rates and favourable mid-term outcomes. Further studies are needed to investigate whether the use of EAM improves overall outcome of conduction system pacing, and to identify specific patient populations who benefit the most from EAM-guided lead implantation.

Isolated PR prolongation in patients undergoing transcatheter aortic valve implantation

Abstract Funding Acknowledgements Type of funding sources: None. Background New conduction disturbances are common complications following transcatheter aortic valve implantation (TAVI). The last ESC guidelines recommended electrophysiological study (EPS) or long-term monitoring for patients with new LBBB above 150 ms or one that is associated with PR prolongation (IIa indication). For patients with preexisting conduction abnormality and further PR or QRS prolongation EPS or long-term monitoring are also recommended but with a IIb recommendation. The data regarding the prognosis and management of patients with isolated PR prolongation is limited. Purpose Evaluate the need for permanant pacmaker implantation, occurance of syncope and mortality during the 1st year following Transcatheter aortic valve implantation Methods All patients undergoing TAVI at Shaare Zedek Medical Center were retrospectively reviewed. All patients underwent at least 1 ECG prior and daily post the procedure. Patients with isolated PR prolongation &amp;gt; 20 ms compared to baseline ECG were included. While patients with preexisting permanent pacemaker (PPM), complete AV block or any peri or post procedural QRS widening &amp;gt; 20 ms were excluded. Patient were followed for 1 year for the occurrence of syncope, PPM or death. Results Excluding patients with preprocedural PPM, 1028 patients were reviewed. Compared to baseline ECG, 124 (12%) patients had isolated PR prolongation, of whom 88 (71%) and 36 (29%) had baseline narrow and wide QRS respectively. During follow-up none of these 88 patients with baseline narrow QRS required in hospital PPM, while only 2 patients with baseline wide QRS required in hospital PPM. During 1 year follow-up, 6 patients (4.8%) died and no one had syncopal episode or need for PPM. Conclusion Post TAVI, isolated new PR prolongation is not associated with an adverse outcome including syncope or progression to complete heart block and need for PPM at 1 year post the procedure. These finding may be considered when evaluating these patients post the procedure.

Electroanatomic mapping system guided His bundle pacemaker implantation: experience of the His bundle registry graz

Abstract Funding Acknowledgements Type of funding sources: None. Background Electric conduction disturbances are very common, however, patients in need for ventricular pacing may suffer from pacing-induced heart failure due to unphysiological pacing by the right ventricular lead. Conducting system pacing allows to overcome this common issue with a more physiologic approach, but real-life procedural data using this technology is scarce. Methods We report a single centre experience of the first 63 consecutive patients being implanted with a His-bundle-based pacemaker 09/2020-11/2022 per 3D-mapping guided implantation due to bradyarrhythmia, or for cardiac resynchronisation therapy in heart failure combined with a left-ventricular lead (HOT-CRT) ± a right ventricular defibrillator lead. The identification of the His-bundle-location was done with a 3D electroanatomic mapping system via an introducing sheath that is provided with electrodes at its tip. Results Mean age was 71 [18;87] years, 18/63 (29%) patients were female, mean baseline LVEF was 46±15%. Baseline ECG was captured before implantation: QRS width was 127±34ms, with typical LBBB in 19/63 (30%), typical RBBB in 5/63 (8%), alternating BBB in two patient (3%) and either no BBB or ventricular escape rhythm in 37/63 (59%). Indications for implantation were AV-block grade II-III in 31/63 (49%), primary prophylactic ICD indication in HFrEF in 18/63 (29%), atrial fibrillation with bradycardic conduction in 8/63 patients (13%), sick-sinus-syndrome in 4/63 (7%) and secondary prophylactic ICD indication in one patient (2%). In 57/63 (90,5%) a primary device was implanted, in 6/63 (9,5%) a pre-existent device was upgraded with a HB lead. Therefore, 23 dual-chamber-pacemaker, 5 single-chamber-pacemaker, 10 single-chamber CRT-P, 17 dual-chamber CRT-P, 4 single-chamber CRT-D, 4 dual-chamber CRT-D were implanted. In 63 patients his bundle pacing was attempted, while in 6/63 (9%) patients outside of this analysis the attempt was not successful, these patients were consecutively implanted with a non-HBP-device and therefor excluded from the further analysis. In the 63 patients included in this analysis with a primary successful pacing at the his-position, 5/63 (8%) his-bundle-leads dislocated within the first 48 hours, leading to a secondary success rate of 92%. There were two post-procedural pneumothorax that needed drainage, no major procedure-related complications occurred. Median skin-to skin procedure time was 111±47 minutes in his-bundle-device-implantation. The paced QRS width at the post-implantation follow up was 113±27ms with a change in QRS width of -15±39ms (+72; -92ms). The mean his-bundle sensing was 5,38±5,6mV and the mean threshold 1,1±0,86V over 1,0±0,5ms (0,4;1,5ms). The proportion of ventricular pacing was 75±36%. Conclusion Electroanatomic-guided His bundle pacing as a new innovative technic for physiological pacing is viable including high implantation success rate as well as electric impact, both regarding QRS width and pacing threshold.

Delayed ventricular conduction alters ventricular repolarization in patients with heart failure: an electrocardiographic imaging study

Abstract Funding Acknowledgements Type of funding sources: Public hospital(s). Main funding source(s): Personal grant from the Dutch Heart Foundation. Background In the normal human heart, the polarity of the T-wave is concordant with the QRS complex. This phenomenon is often explained by longer repolarization of earlier activated regions. Patients with delayed ventricular conduction often have discordant T-waves, but the link to regional repolarization is unknown. Aim To compare epicardial repolarization-activation (RT-AT) relations in patients with heart failure and reduced ejection fraction (HFrEF) with those having a structural normal heart. Methods 14 patients with HFrEF and delayed ventricular conduction and 11 patients no history of structural heart disease and a normal surface ECG (nQRS) were analyzed using electrocardiographic imaging (ECGI). HFrEF patients were subcategorized as left bundle branch block (LBBB, n=6) or non-specified intraventricular conduction disturbance (IVCD, n=8). Noninvasive ECGI was used to assess epicardial activation (ATs) and repolarization times (RTs). RT-AT relationships were evaluated for 24 epicardial segments using linear regression analysis. Interventricular repolarization dispersion (inter-RTD) was defined as the difference between average left-ventricular (LV) and right-ventricular RT, while total epicardial repolarization dispersion (total-RTD) was defined as the standard deviation of all epicardial RTs. The maximum of the local RT gradients (RTG) was defined as their 95th percentile. RT parameters were described as median±IQR and Kruskal Wallis tests were used to evaluate the differences between the groups. Results An HFrEF patient’s representative 24-segment AT and RT bullseyes with a positive RT-AT relation (~depolarize last, repolarize last) is provided in Figure1A. A positive RT-AT slope was present in the majority of HFrEF patients (1.14±0.17 for LBBB and 1.16±0.55 for IVCD), whereas the nQRS group (-0.25±2.16) demonstrated an overall slightly negative slope with high variability (Figure 1B and 1C). Individual (thin lines) and group-averaged (thick lines) RT-AT slopes normalized for the earliest AT and earliest RT (in case of a positive RT-AT slope) or latest RT (in case of a negative slope) are visualized in Figure 1C. Both inter-RTD (41±25 for LBBB, 32±13 ms for IVCD, and 8±20 ms for nQRS) as well as total-RTD (34±9for LBBB, 34±12 ms for IVCD, and 24±8 ms for nQRS) was significantly higher in the LBBB and IVCD group compared to the nQRS group, whereas RTG did not differ between the groups (Figure 1B). RT-AT slopes, inter-RTD, total-RTD, and RTG did not significant differ between the LBBB and IVCD subgroup. Conclusion This ECGI study shows that in patients with HFrEF, later activated regions also have a later completion of repolarization, regardless of conduction delay, whereas a variable RT-AT relation is present in subjects with structural normal hearts. HFrEF additionally initiates a higher degree of interventricular and total repolarization dispersion.

Pitfalls and limitations in the assessment of the HV interval in a transcatheter aortic valve replacement population. A prospective analysis

Abstract Funding Acknowledgements Type of funding sources: None. Introduction identification of patients with new-onset conduction disturbances at risk of AV-block remains a major unmet challenge in Transcatheter Aortic Valve Replacement (TAVR). His-Ventricular interval (HVI) measurement has been proposed in patients at risk. However, the HVI assessment is often overlooked, performed as a single assessment without active mapping, and even single-catheter assessment is sometimes performed. Purpose To systematically evaluate HVI measurements in a post TAVR population, in search of methodological pitfalls as related to outcomes Methods Consecutive patients who underwent HVI assessment post-TAVR between June 2014 and December 2021. HV interval was classified as normal (&amp;lt;55), intermediate (55-70) and abnormal (&amp;gt;70 ms). Incremental atrial pacing was performed whenever possible. All tracings were reviewed by two blinded operators. Pitfalls in the assessment of atrioventricular conduction were categorized into types 1 to 5, as reported in Table 1. In sinus rhythm, only proximal HVI were considered defined as the concomitant recording of a near-field atrial signal. Results 90 cases were analyzed; median age 81 years1 [76 – 86] years; 37 (41%) male. The median HV interval was 54 [50 – 65] ms. An abnormal HV interval, exceeding the 55 and 70ms cut-off values, was found in 41 (45.9%) and 13 (14.8%) patients, respectively. At least one pitfall was found in 15 patients (16%). Short-term AV block occurred in 3 patients in sinus rhythm in whom no incremental pacing was performed, and in 2 patients with AF despite normal or borderline HVI in both groups. Conclusions Pitfalls in the assessment of the HVI are often observed after TAVR. Identification of infra- and especially intra-His disorders requires careful mapping and must be an active process on behalf of the operator. Our results call into question the value of the HV assessment using a single catheter or in patients with atrial fibrillation, considering the value of incremental atrial pacing and the inherent limitations in AF to assess the most proximal His or intraHis block.

Transcatheter Aortic Valve Implantation: Addressing the Subsequent Risk of Permanent Pacemaker Implantation.

Transcatheter aortic valve implantation (TAVI) is now a commonly used therapy in patients with severe aortic stenosis, even in those patients at low surgical risk. The indications for TAVI have broadened as the therapy has proven to be safe and effective. Most challenges associated with TAVI after its initial introduction have been impressively reduced; however, the possible need for post-TAVI permanent pacemaker implantation (PPI) secondary to conduction disturbances continues to be on the radar. Conduction abnormalities post-TAVI are always of concern given that the aortic valve lies in close proximity to critical components of the cardiac conduction system. This review will present a summary of noteworthy pre-and post-procedural conduction blocks, the best use of telemetry and ambulatory device monitoring to avoid unnecessary PPI or to recognize the need for late PPI due to delayed high-grade conduction blocks, predictors to identify those patients at greatest risk of requiring PPI, important CT measurements and considerations to optimize TAVI planning, and the utility of the MInimizing Depth According to the membranous Septum (MIDAS) technique and the cusp-overlap technique. It is stressed that careful membranous septal (MS) length measurement by MDCT during pre-TAVI planning is necessary to establish the optimal implantation depth before the procedure to reduce the risk of compression of the MS and consequent damage to the cardiac conduction system.

New insights into the correlation between genotype and cardiac phenotype in laminopathies

Abstract Funding Acknowledgements Type of funding sources: None. Background Genotype-phenotype correlation and risk stratification for heart failure progression in patients with cardiolaminopathies are poorly defined. Purpose The primary aim of the present study is to characterize and correlate phenotype with genotype and sex. The secondary aim is to test the two main existing prognostic scores (the Arbustini and the Whabi score), both developed to predict ventricular arrhythmic events in cardiolaminopathies, for both major ventricular arrhythmias (MVA) and end-stage heart failure (ESHF). Methods This is a retrospective, single-center study, including patients with lamin (LMNA) and/or emerin (EMD) genetic variants. Data were collected from the first medical contact (FMC) to the last follow-up (FU). Results 28 patients (57% male, 82% probands, 68% with a family history of sudden death) were included: 96% harbored LMNA heterozygous variants, 15% had non-missense variants, 11% had variant previously never described. Functionally, 50% were variant of undetermined significance (VUS, C3), the rest were either pathogenetic or likely pathogenic (C4/C5) variants. Median age at FMC was 41 years (IQR 30-55 years), median FU was 11 years (IQR 8-18 years). At FMC, all patients had cardiac involvement, 54% had muscle involvement. By the last FU, 54% developed atrial fibrillation, 43% atrioventricular block (AVB) &amp;gt; I degree, 50% carried an implantable cardioverter defibrillator (21% with resynchronization), 50% had suffered at least one episode of MVA, 25% developed ESHF: 11% died due to refractory HF, 14% underwent heart transplantation (mean age 43.5 ± 9 years). The age of onset of the different types of cardiac phenotype was not influenced by sex. The penetrance of atrioventricular (AV) conduction defects (Figure 1 Panel A) and of atrial tachyarrhythmias (Figure 1 Panel B) was higher and earlier in subjects with non-missense variants. Subjects with VUS, compared to those with pathogenetic/likely pathogenetic variants, showed a significantly lower and later penetrance of MVA (Figure 2 Panel A) and a later penetrance of non- sustained ventricular tachycardia (NSVT, Figure 2, Panel B), but not of AV conduction disturbances, atrial arrhythmias, or contractile dysfunction. Arbustini score at FMC proved to be a predictor of both MVA and ESHF, while Whabi score only predicted MVA. Conclusions In our series, the prevalence and the age of appearance of the different cardiac phenotypes of cardiolaminopathies were not influenced by sex, while the presence of VUS correlated with a lower risk of ventricular arrhythmias, but not of the other cardiac manifestations including contractile disfunction and heart failure. Our data suggest the importance of a close cardiac monitoring and of larger prospective studies even in patients with VUS. All patients developed a sever cardiac phenotype by the age of 60.

Аnalysis of preoperative and postoperative electrocardiogram in children with total anomalous pulmonary venous connection

Introduction. TAPVC is a condition that requires diagnosis and surgical treatment in a short period of time. As the result of an absence of the direct connection between pulmonary veins and left atrium, systemic and pulmonary venous return drainage to the right heart with volume and pressure overload. At the same time, left heart preload is depending on atrial septal defect. The hemodynamic features of the TAPVC create conditions for abnormal spread of electric impulses, whereas necessity of surgical reconstruction on the atrial level — reasons for rhythm and conduction disturbance in postoperative period.Aim of the study: detection of specific EKG markers of TAPVC for differential diagnosis of critical conditions in children, analysis of basis preand postoperative EKG to determine EKG pattern in children with TAPVC, registration of EKG changing in early and late postoperative period to define the potential rhythm and conduction disturbance in patients with TAPVC.Materials and methods. The data of biventricular TAPVC patients were reviewed. We estimated characteristic of P, PQ, QRS, QT, rhythm and conduction disturbance and evaluated preand postoperative EKG data, with their comparison in 30 patients. Results. Preoperative EKG (9,3 ± 6,5 days) showed sinus rhythm in all cases, P wave was 62,6 ± 10,6 (40–80) msec, PQ — 104,1 ± 15 (80–160) msec, QRS — 64,3 ± 13,5 (40–100) msec, QT — 253,1 ± 29,5 (210–350) msec, electric axis of the heart — 130,9 ± 44,4 (-70 ± 185). Postoperative rhythm was sinus in 83,3 % cases, atrial ectopic — 13,3 %, AV node rhythm — 3,3 %. The comparison of preand postoperative EKG data showed significant (p &lt; 0,05) difference in P, QT, and electric axis of the heart measurements. In late postoperative period we detected non-pathological differences in P, PQ, QRS, QT compared early posleoperative period, but sinus node dysfunction frequency was high in late postoperative period.Conclusion. There are no specific ECG markers in preoperative TAPVC patients. The standard EKG showed right heart volume and pressure overloud with positive changing of it after surgical correction of TAPVC. The early postoperative EKG did not showed “typical” rhythm and conduction disturbance after surgery at the atrial level, but patients require a long-time dynamic observation after TAPVC surgery because of higy frequency of sinus node dysfunction in late postoperative period.

P22 AN UNEXPECTED DIAGNOSIS; GEMELLA MORBILLORUM, A POORLY KNOWN KILLER

Abstract 58–year–old woman, previous smoking habit. In medical history holosystolic murmur since childhood. At echocardiogram performed in 2019: "VS with preserved FE, mild–to–moderate IA, likely perimembranous DIV." No major comorbidities. In June 2021, she was admitted to the Mestre NICU for paroxysmal complete atrioventricular block. On echocardiogram, mild worsening of IA was described, with a sub–valvular shunt and doubtful aortic bicuspidia. At 24 hours after admission, the patient underwent definitive bicameral PM implantation. In light of the clinical and echocardiographic suspicious, we began to think of a possible organic genesis of the event; a hypothesis supported by the finding of serotin fever and a dental examination with dental hygiene that the patient reported having performed a month earlier. So, on suspicion of an infectious genesis, cold blood cultures were requested and found to be positive for Gemella Morbillorum. The endocarditis hypothesis was confirmed by performing a TE echo and PET/CT scan. Antibiotic therapy was then set up, and an infectious source was subsequently searched for, through a CT scan of the dental arches, which was positive for foci of periodontopathy, and through a rectosigmoidocolonoscopy finding an adenoma with high–grade dysplasia. HOT TOPIC: infective endocarditis is a disease with a high risk of mortality and complications. Among the complications, conduction disturbances are relatively rare. A–V block is often paroxysmal, driven by inflammation, and therefore potentially reversible. Hence, the paramount importance of performing a thorough echocardiogram and resolving any suspicions before referring the patient for definitive device implantation. The case also turns out to be particularly interesting not only for the onset of symptomatology but also for the etiology of the latter. In fact, the microorganism responsible is not among the most frequent germs but represents a rare cause of which there are few cases described in the literature. The main infectious source in humans is the dental system, but several studies have shown a correlation between Gemella morbillorum and rectal colon cancer. Ultimately, the above case represents a typical example of how a "easy" hospitalization for a conduction disorder can actually reveal a much more complex pathology.

P423 RELAPSE OF ACUTE MYELOID LEUKEMIA WITH CARDIAC INFILTRATION: A CASE REPORT

Abstract We describe the case of a 42–year–old man who presented to the emergency department suffering from asthenia, dyspnea and tachycardia. The patient had been diagnosed, two years earlier, with acute myeloid leukemia (AML), treated with two lines of chemotherapy and allogeneic bone marrow transplantation from a family donor. Atrial fibrillation with rapid ventricular response was documented at the ECG. The echocardiogram showed moderate left ventricular dysfunction in the presence of dishomogeneous thickening of left and right ventricular wall and a severe circumferential pericardial effusion causing cardiac tamponade, with the need of urgent pericardiocentesis. AML relapse was documented at the laboratory tests. The suspected cardiac involvement was investigated with cardiac MRI which documented thickening and diffuse late gadolinium enhancement at the level of the left and right ventricular wall, the interatrial septum and the atria walls. The pericardium and the epicardial fat were also thickened and endowed with contrast enhancement. A lymphocyte assay was performed on pericardial fluid and showed the presence of a blast population (approximately 27% of white blood cells) with variable expression of myeloid antigens. The clinical, radiological and finally immunophenotypic picture therefore concluded with relapse of acute myeloid leukemia with myocardial and pericardial infiltration. Acute myeloid leukemia usually presents with symptoms related to bone marrow failure. Clinically significant cardiac involvement is rare but should be considered when cardiorespiratory symptoms occur. Cardiac manifestations include coronary artery disease, heart failure, conduction disturbances, myocarditis, pericarditis, and pericardial effusion. Understanding the underlying pathophysiology and recognizing potential cardiac manifestations could help in the early diagnosis, evaluation, and treatment of these patients. Echocardiography or cardiac MRI could reveal morphological, structural and signal abnormalities of the cardiac structures and therefore should raise the suspicion of a possible myocardial infiltration by leukemia cells, both in patients with a positive history of leukemia and in those in whom cardiac involvement could represent the first manifestation of a hematological pathology.

P295 WHEN TAVI IS THE RIGHT CHOICE

Abstract Clinical case We describe a case of a 62–y–old man, affected by hypertension, insulin–dependent diabetes mellitus, advanced liver cirrhosis. After screeing, the patient was listed for liver transplantation. On September 2022, the patient was admitted to our Emergency Room due to HF in class NYHA III. The transthoracic echocardiogram showed a severe aortic regurgitation with mobile vegetations, the largest of which is more than 10 mm on the right aortic cusp. Normal biventricular function was observed with sPAP of 45 mmHg. Thus, we concluded for post–endocarditis severe aortic regurgitation. We discussed tha case in our Department Heart Team with the concomitant presence of the Liver Team. We considered the patient at high surgical risk, mostly due to the risk of postoperative hepatic insufficiency. So, we decided for a TAVI off–label. So, we impantanted a Sapien 3 Ultra 26 mm through transfemoral access. To reduce the risk of cerebral embolization, we used Triguard 3 system, while to prevent coronary embolization we used a closed stent into the right coronary ostia, ready to be opened. The patient was discharged in the fourth postoperative day, without conduction disturbances. The postoperative echo showed normal valvular function and absence of paravalvular leakages. Conclusions Patients with advanced liver cirrhosis are at risk of organ failure following use of extracorporeal circulation. In selected patients, TAVI may be a valid alternative. The peculiarity of the specific case was due to the use of the TAVI in an off–label procedure of aortic insufficiency with the simultaneous presence of mobile vegetation at high embolic risk.

P5 DISCOVERY OF A NEW HATTR GENETIC VARIANT: A CASE REPORT OF A PATIENT WITH CARDIAC UPTAKE AT 99–MTC–DIPHOSPHONATES SCINTIGRAPHY AND ABNORMAL MONOCLONAL PROTEINS TESTS

Abstract Introduction Cardiac amyloidosis is an infiltrative disease that remains an under–diagnosticated cause of heart failure. Diagnostic algorithms focus on identifying the two most frequent forms of the disease, light chains amyloidosis (AL) and transthyretin amyloidosis (ATTR), by the initial use of 99mTc–DPD scintigraphy coupled to assessment of monoclonal proteins. Etiological distinction is and of pivotal importance since the availability of specific disease modifying treatments. Case Description We report the case of a 61–year–old man hospitalized for new onset of heart failure. Past medical history highlights bilateral carpal tunnel syndrome and monoclonal gammopathy of undetermined significance (MGUS). Cardiovascular examination reveals clinical signs of pulmonary and peripheric congestion. ECG shows conduction disturbances and low QRS voltage. Transthoracic echocardiography reveals left ventricular hypertrophy, normal systolic function (LVEF 58%), 3rd degree LV diastolic disfunction and mild pericardial effusion. Laboratory tests shows abnormal levels of TnT and pro–BNP. A diagnosis of cardiac amyloidosis is considered, and further exams are executed: cardiac magnetic resonance, haematological laboratory tests and 99mTc–DPD scintigraphy (tab. 1). Since both bone scintigraphy and monoclonal proteins tests are positive, diagnosis of cardiac amyloidosis cannot be made without non–invasive modalities (fig.1) and the patient is referred to an Amyloidosis Centre. Haematological evaluation and abdominal fat pad biopsy show stability of haematological disease and confirms the deposition of amyloidogenic TTR both in wild–type and mutated Ile88Arg variants. The results of genetic analysis confirms the presence of a heterozygous mutation of TTR gene (p.Ile88Arg – c.263T&amp;gt;G) (fig. 2). This mutation is not reported in database ClinVar nor in gnomAD, but according to the ACMG criteria it can be considered likely pathogenic. Considering the final diagnosis of cardiac hATTR the patient is considered eligible for treatment with Tafamidis. Discussion and Conclusion Despite clinical history with cardiac conduction system abnormalities and bilateral carpal tunnel syndrome, some gene TTR variants can bring false negative results at 99mTc–DPD scintigraphy, so ATTR form should not be excluded basing on non–invasive modalities. Performing a compete diagnostic workup led us to discover a new TTR pathogenic variant and confirm ATTR form without performing endomyocardial biopsy.